Fuse.



G. DENMAN 61E. F. LEWIS.

FUSE.

APPucATloN man 11,111.21. 191s.

1,294,880. Patented 11011.18, 1919.

WITNESSES FIOM eww/WHA@ A TTHNEYS UNITED srATEs PATENT 0ppm@ GEORGE DENMAN AND EDWARD F. LEWIS, 0F TERRE HAUTE, INDIANA.

. FUSE.

To all whom 'it may concern Be it known that we, GEORGE DENMAN and EDWARD F. Lnwrs, citizens of the United States, and residents of Terre Haute, in the county of Vigo and State of Indiana, -have4 made certain new and useful Improvements in Fuses, of which the following is a specification.

Our invention is an improvement in fuses and has for its object to provide a fuse consisting of a primary and auxiliary fuse s o arranged in the circuit that when the primary -fuse is burned out, the current will be automatically transferred to the secondary auxiliary fuse, without any interruption to the service.

In the drawing: i

Figure l is a front v'iew of the improved fuse, l

Fig. 2 is' a section on the line 2-2 of Fig. i 1, looking in the direction of the arrows ad' jacent to the line, and

Fig. 3 isa sectional View ofthe primary fuse.

In the present embodiment of the invention a suitable base 1 is provided upon which,

the fuses are mounted. the secondary or auX- iliary fuse 2 being of the usual or ordinary construction, and being held on the b ase by the usual clips 3. p n

The primary fuse consists of a cylindrical body 4, having 'a cap 5 at its lower end, and having a sleeve 6 at its upper end, the said sleeve being of conducting material, and the upper end of the sleeve is flush with the upper end of the body 4.

A cap 7 is provided for covering the top of the body and the sleeve, the cap fitting around the body and sleeve, and it will be noticed that the body, the ,sleeve and the cap v7 have registering openings at the top of the sleeve and body, for permitting access to mechanism to be later described arranged within the casingfor the fuse.

Holding clips 8 and 9 are provided for the casing, and the clip 8 is at the sleeve 6, and engages said sleeve as shown. The yclip 9 is at the cap 5 and engages the cap, and a contact plate 10 is arranged on the base at the cli-p 8, the said plate beingc'onnected to the clip and the sleeve 6.

The lead wire`11 from thprimary line is i 4 and body.

` this cap Specification of Letters Patent. .Patented Febo 18, 1919 Applicationrled March 27, 1918. Serial N o. 224,952. i i

otal connection 14 ofthe switch lever and l I passes from a binding post 18 connectedtoI the clip 3 and a lead wire 19 connects the clip 9 of the primary fuse with the clip 3 ofthe secondary or auxiliary fuse.

The fuse 20 of the primary fuse is connected at its upper end to a depending lug 21 on the cap, by means of a. screw 22, which is accessible through the registering openings, before mentioned, in the cap, sleeve The' lower end of the fuse 20` is connected to a binding post 23 on a lug 24 depending from the cap 5 and the Ifuse 20 'is inclosed by a tube 25 of insulating material, as for instance, fiber.

to the secondary fuse The cap 7 is movable on the sleeve and is normally pressed upward by a coil spring 26 arranged within the fuse casing between the cap 7 and a stop 27 in the formpf a collar on the tube 25. A contact plate 28 is secured to the base above the cap 7, and in position to be engaged thereby, when the cap is moved upward by the spring under conditions to be later mentioned, and this contact plate is connected with the lead wire 16. v.

In operation under ordinary conditions the current passes by way-.of leadw-ire 11, the contact plate 10, the sleeve 6 and the cap 7, through the fuse-2O and by way of the lead wires 19 and 17 to thel transformer. Should the fuse 25 burn out, the cap 7 will be no longer restrained, and the spring 26 -will lforce the-cap up into contact with the is connected with the binding post 23 at its lower end, the cap is depressed and the 11pper end of the fuse wire is connected to the lever 21, and the fuse then holds the'spring under compression. The switch lever 13 is current may be passed through the said fuse,

and in case there is still trouble in the trans- -former, the small fuse will blow.

lt will be understood that in placing the fuse wire 20 it is irst connected with the binding post 22.

We claim:

1. A device of the character specied, comprising a primary and a secondary fuse., the primary 'fuse having at each end a cap, and the cap at the upper end being movable, a spring normally pressing thecap upward, a fuse Wire arranged between the caps and normally holding the spring under compression, a contact plate arranged above the primary fuse and in position to be engage by the cap when it is vforced upward by the spring, a lead wire connected to the plate and to one end of the secondary ruse, a lea wire connected with the lower cap oiE the primary fuse and with the other end of the secondary fuse, a conducting sleeve on the primary fuse upon which lthemovable cap moves, the line wire being connected with the said sleeve and a switch for connecting the line wire directly with the'lead wire of the contact plate.

2. A device of the character specified comprising a primary and a secondary fuse, said primary fuse comprising a casing, having a movable cap at its upper end to which the fuse wire is connected, a spring normally forcing the cap upward, a fuse wire holding or" l, and

trouble develops in the Y incasso the spring under compression, the primary fuse being interposed in the line wire, a contact plate above the movable cap and. adapted to be engaged thereby when the cap is moved upward' by the spring, and a connection between the plate and the secondary fuse "for interposing the secondary fuse in the line wire when the cap engages the plate, and means for cutting out the primary fuse from the line wire and for cutting in the secondary fuse.

3. A device .of the character specified comprising a primary and a secondary fuse, said primary fuse comprising a casing, having a movable cap at its upper end to which the fuse wire is connected, a spring normally forcing the cap'upward, a fuse the spring under compression, the primary fuse being interposed in the line wire, a contact plate above the movable cap and adapted to be engaged thereby when the cap is moved upward by the spring, and a connection between the plate and the secondary fuse for interposing .theitsecondary fuse 1n the line wire when the cap engages the plate.

4. A device of the character specified comprising a primary and a secondary fuse, connections between the corresponding terminals at the ends of the fuses, the end of one fuse being adapted for connection with one terminal of a line and the other end of the other fuse with the other terminal of the said line, one of the said connections between the ends of the fuses being normally interrupted, a movable portion on the primary fuse for closing the said connection and normally held by the fuse out ot engaging position, anda spring pressing the movable portion in a direction to close the said connection. v

GEORGE DENMAN. EDWARD F. LEVVlS.

Witnesses:

ROBERT M. ATKINS, XERXES C. SrARirs.

wire holding 

